/* jQuery Session vars v.0.3
 * by Jay Salvat
 * http://www.jaysalvat.com
 * -----------------------------------------------
 * Inspired by an idea from Mario Heiderich
 * http://code.google.com/p/quipt/
 * -----------------------------------------------
 * Requires jquery.json.js by DeadWisdom
 * http://code.google.com/p/jquery-json/
 * -----------------------------------------------
 * CHANGELOG
 * 0.3 -- 11-JUL-08
 * Security improvements
 * Calling manually sessionStart and sessionStop is not required anymore
 * Window.name is keept between pages
 * 0.2 -- 10-JUL-08
 * Now works with functions, objects and arrays
 * 0.1 -- 08-JUL-08
 * First draft
 * -----------------------------------------------
 * USAGE
 * - To Store
 * $(function() {
 *      $.session("myVar, "value");
 * });
 * 
 * - To Read
 * $(function() {
 *      alert( $.session("myVar) );     
 * });
*/
(function($) {
	var sessionData = {};
	var windowName  = "";
	var domain     	= location.href.match(/\w+:\/\/[^\/]+/)[0];
	var referrer   	= (document.referrer) ? document.referrer.match(/\w+:\/\/[^\/]+/)[0] : "";

	if(referrer == "" || referrer !== domain) {
			window.name = window.name.replace("#"+domain+"#", "");
	}
			
	function loadData() {
			stored = window.name.split("#"+domain+"#");
			windowName = window.name = stored[0];
			if (data = stored[1]) { 
					$.each(data.split(";"), function(i, data) {
											parts           = data.split("=");
											varName         = parts[0];
											varValue        = unescape(parts[1]);
											sessionData[varName] = varValue;
					});
			}
	}
	
	function saveData() {
			var dataToStore = windowName+"#"+domain+"#";
			$.each(sessionData, function(varName, varValue) {               
							if (varName && varValue) {
									dataToStore += ( varName + "=" + escape( varValue ) + ";" );
							}
			});
			window.name = dataToStore;
	}
	
	$.session = function(name, value) {
			if (value) {
					if ($.isFunction(value)) {
									value = value();
					}
					if ( $.toJSON ) {
							sessionData[name] = $.toJSON(value);
					} else {
							sessionData[name] = value;
					}
			} else {
					if ( $.evalJSON ) {
							return $.evalJSON(sessionData[name]);
					} else {
							return sessionData[name];
					}
			}
	}
	
	$.sessionStop = function() {
			saveData();
	}               
	
	$.sessionStart = function() {
			loadData();
	}

	$.sessionStart();
	window.onunload = function() { $.sessionStop(); };
	
})(jQuery);
